JP2002059799A - Airbag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an airbag at low manufacturing costs, while increasing the volume of the portion of the airbag corresponding to an occupant's abdomen for increased safety, and using an arrangement composed of a small number of simple ground fabrics to enhance coupling workability. SOLUTION: The airbag 1 is formed by coupling two vertically split ground fabrics 3 and 4 together; the ground fabrics 3 and 4 have expanded shapes formed with respective rear face portions 3c and 4c which face an occupant H when the airbag is inflated, respective side portions 3b and 4b supporting the rear face portions 3c and 4c, and an upper face portion 3a and a bottom face portion 4a, respectively. The upper and lower ground fabrics 3 and 4, formed into approximately box shapes by coupling the respective side portions 3b and 4b and the upper face portion 3a or the bottom face portion 4a to the respective rear face portions 3c and 4c, are coupled together at their overlapping portions, whereby the airbag 1 is formed in the shape of a bag. Coupling lines 15, 16 and 18 between the rear face portion 4c and the side portion 4b of the lower ground fabric 4 are formed in a truncated chevron shape using at least two lines which converge on the outside, and a projecting part 20 is formed at the rear face portion 4c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag used for vehicles such as vehicles, airplanes, automobiles, etc., and more particularly to an airbag which is formed three-dimensionally and which is most suitable for a passenger seat of an automobile having a large volume. It is.

[0002]

2. Description of the Related Art In general, as an airbag device, an airbag and an inflator are housed in a module provided in an in-vehicle equipment, and the airbag is inflated by a gas blown from the inflator to a vehicle interior side to protect an occupant. It has a structure. In-vehicle equipment for installing airbags,
There are steering wheel center pads, instrument panels, door trims and seats.

[0003] In particular, since the distance between the instrument panel and the occupant is large, the passenger seat airbag is required to have a large volume when inflated, and the inflated shape is three-dimensionally deployed to protect the occupant. Is required.

An example of such a passenger airbag is disclosed in Japanese Patent Application Laid-Open No. Hei 10-315892. The base fabric constituting the airbag has a structure including three base fabrics: a pair of side fabrics and a main fabric. However, an airbag composed of three base fabrics has a problem that the number of components is large and it is necessary to sew three-dimensionally.

[0005] FIG. 6 shows a proposal proposed in consideration of such a problem (see Japanese Patent Application Laid-Open No. 9-99795). This airbag A is 2
Since the base fabrics B and C are overlapped in the vertical direction and their peripheral edges are joined by sewing or the like, they are excellent in terms of reducing the number of parts and improving workability.

[0006]

However, in such a conventional airbag A, upper and lower base fabrics B and C are provided.
Are set in the same shape, there is a possibility that a gap S is formed between the occupant H and the abdomen H1 when inflated. Also,
As shown in FIG. 7, when the occupant H is seated on the front side and is in contact with the lower fabric C on the lower side of the airbag A, the occupant H is pressed by the chest H2 of the occupant H and displaced in the G direction. There is a risk that it will.

SUMMARY OF THE INVENTION An object of the present invention is to provide an airbag which can securely hold an occupant's abdomen and, at the same time, has a small and simple base fabric structure, improves the workability of connection, and is inexpensive to manufacture.

[0008]

According to the first aspect of the present invention,
The two base cloths divided in the vertical direction are formed by joining together, and each base cloth has a rear surface portion facing the occupant when inflated, and both side portions, the upper surface portion or the bottom portion supporting the rear surface portion. It has a formed unfolded shape, and is formed in a bag-like shape by joining the overlapping portions of the upper and lower base fabrics that have become substantially box-shaped by joining the two side portions, the upper surface portion or the bottom portion to the rear surface portion, respectively. A connecting line between a rear surface portion and a side portion of a lower base fabric is formed in a horizontal C-shape by at least two lines converging on the outside to form a bulging portion on the rear surface portion. .

According to the first aspect of the present invention, since the volume of the lower base cloth that contacts the abdomen of the occupant can be increased, the safety for the occupant is improved. Furthermore, since the airbag has a simple structure composed of two base cloths, and the length of the overlapping portion of the upper and lower base cloths does not need to be changed, the work of stacking the upper and lower base cloths is also changed from the conventional case. It can be carried out without any problems and the workability is good, and the manufacturing cost can be reduced.

According to a second aspect of the present invention, the two connecting lines of the rear surface portion and the side portion of the lower base fabric are each formed by an arc curved toward the inside of the airbag, and the two connecting lines are formed. The lines are connected smoothly via a third connecting line formed by an arc.

[0011] According to the second aspect of the present invention, the swelling portion is 3
Since the bulges are formed by continuous arcs on the sides, the surface shape of the bulging portion in contact with the abdomen of the occupant can be formed smoothly, and safety is improved.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to FIGS.

The airbag 1 according to this embodiment is for a passenger seat installed in an instrument panel 2 located below a front window panel W. This airbag 1 has a non-coated basis weight of 200 g /
and a two base cloths 3, 4 made of nylon 66 ^woven fabric m ^2.

The developed shape of the base fabrics 3 and 4 will be described with reference to FIG. In FIG. 2, the upper side is the side attached to the instrument panel 2 in front of the vehicle, and the lower side is the side facing the occupant H behind the vehicle.

The base fabric 3 is located on the upper side, is symmetrical as a whole, and has a substantially triangular side portion 3b formed on both sides of a rectangular upper surface portion 3a.
A substantially semicircular rear surface portion 3c is formed on one side of the rear end of “a”. A vent hole 7 for releasing gas after expansion is formed at a boundary portion between the upper surface portion 3a and both side portions 3b.

The total width W3 of the base cloth 3 is 1100 mm and the total length L
3 is 1015 mm, and the hypotenuse 9 is 680 mm.
The side 8 has a length of 330 mm, the side 12 has a length of 550 mm, and the side 10 is formed of an arc having a radius of 500 mm.

The base cloth 4 is located on the lower side, is symmetrical as a whole, and has substantially rectangular side parts 4b formed on both sides of a rectangular bottom part 4a.
A substantially rectangular rear surface portion 4c is formed on one side of the rear end of “a”. A gas inlet 5 is formed at the front end of the bottom portion 4a, and an inflator (not shown) is connected to the gas inlet 5 so that gas can be introduced. A small hole 6 is formed around the gas inlet 5 for pushing a bolt of a retainer (mounting fitting) for attaching the airbag 1 to the reaction can. The peripheral portions of the gas inlet 5 and the small hole 6 are reinforced by sewing a reinforcing cloth (not shown).

The total width W4 of the base cloth 4 is 1100 mm and the total length L
4 is 1110 mm and the hypotenuse is 680 mm. The side 13 is 330 mm, and the side 19 is 550 mm.
Each of the sides 15 and 16 constituting the bulging portion 20 has a radius of 50.
The side 17 is formed by an arc having a radius of 100 mm. Since the bulging portion 20 is formed by a continuous arc of three sides, the surface portion of the bulging portion 20 that comes into contact with the abdomen of the occupant H can be formed smoothly, and safety is improved.

As shown in FIG. 2, the base cloths 3 and 4 are formed from the upper surface 3a, the bottom surface 4a and the sides 8 and 13 to the oblique sides 9 and 14.
, The shape of the joints with the rear surfaces 3c, 4c of the side portions 3b, 4b is different, and the shapes of the rear surfaces 3c, 4c sewn correspondingly are also different.

Next, a process of connecting the base fabrics 3 and 4 and sewing them to the airbag 1 will be described. The base fabrics 3 and 4 are full width W3 and W
Since the length 4 and the oblique sides 9 and 14 have the same length and the same inclination angle, the upper half in FIG. Therefore, the three oblique sides 9 and 14 of the base fabrics 3 and 4 and the three sides 8 and 13 are sewn with a sewing machine. For example, in the sewing operation, the upper and lower threads are each made of nylon 66 thread No. 8, and a stitch of 3.5 / cm is performed with a 21 st sewing machine needle. The conditions of the sewing work described below are the same as those of the present work. Then, when side 12 and side 19 are overlapped and sewn,
The base fabrics 3 and 4 are each formed in a substantially box shape.

Next, the overlapping portion 8 of the base fabric 3 having a substantially box shape,
9 and 12 and the overlapping portions 13, 14 and 19 of the base cloth 4 are sewn to form the bag-shaped airbag 1. Base cloth 3 to side 12
a is picked up and the sides 10 and 11 are overlapped and sewn.
Further, the side 19a is turned upside down, the side 19a is picked up, and the side 15,
16, 17 and the side 18 are overlapped and sewn. Finally, the airbag 1 is turned over through the gas inlet 5 to complete the sewing operation. An overlap line J along the front-rear direction appears at the center in the vertical direction of the side portions 3b, 4b. In this manner, the three-dimensional airbag 1 can be formed by a simple operation of merely sewing the two base cloths 3 and 4 together, so that the workability of the sewing is greatly improved.

In the airbag 1 thus formed, the volume of the portion corresponding to the abdomen H1 of the occupant H increases when inflated as shown in FIG. 3, so that the displacement in the G direction as shown in FIG. Is extremely small.

FIG. 5 shows a comparison of the side shapes of the airbag of the conventional example and the airbag of the present embodiment.
m), the length up to the rear surfaces 3c, 4c is 330 mm in the conventional example (L0) and 420 mm in the present embodiment (L). The distance can be reduced by as much as 27%.

[0024]

According to the first aspect of the present invention, the volume of the lower backing cloth that contacts the abdomen of the occupant can be increased, so that the safety for the occupant is improved. Furthermore, since the airbag has a simple structure composed of two base cloths, and the length of the overlapping portion of the upper and lower base cloths does not need to be changed, the work of stacking the upper and lower base cloths is also changed from the conventional case. It can be carried out without any problems and the workability is good, and the manufacturing cost can be reduced.

According to the second aspect of the present invention, the bulging portion is formed by three
Since the bulges are formed by continuous arcs on the sides, the surface shape of the bulging portion in contact with the abdomen of the occupant can be formed smoothly, and safety is improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an inflated state of an airbag according to an embodiment of the present invention.

FIG. 2 is a plan view showing each base cloth of FIG. 1;

FIG. 3 is a side view showing an inflated state of the airbag of FIG. 1;

FIG. 4 is a side view showing a state where an occupant is in contact with the airbag of FIG. 3;

FIG. 5 is a side view showing a difference between a conventional example and an airbag in an inflated state of the present invention.

FIG. 6 is a side view showing an inflated state of a conventional airbag.

FIG. 7 is a side view showing a state where an occupant is in contact with the airbag of FIG. 6;

[Explanation of symbols]

 H Occupant 1 Airbag 3, 4 Base cloth 3a Top surface 4a Bottom portion 3b, 4b Side portion 3c, 4c Rear surface 15, 16, 17, 18 Bonding line 8, 9, 12, 13, 14, 19 Overlapping portion 20 Inflation Departure

Claims (2)

[Claims] 1. A base fabric which is formed by joining two base fabrics divided in a vertical direction, wherein each base fabric is opposed to an occupant when inflated, both side portions supporting the rear face portion, and a top surface portion. Or by having the unfolded shape with the bottom part formed, by joining the overlapping parts of the upper and lower base cloths that are almost box-shaped by joining the two side parts, the top part or the bottom part to the rear part, respectively. An airbag formed in a bag shape, wherein a connecting line between a rear surface portion and a side portion of the lower base fabric is formed in a horizontal C shape by at least two lines converging on the outside, and An airbag, wherein a bulging portion is formed on a surface portion. 2. The airbag according to claim 1, wherein the two connecting lines of the rear surface portion and the side portion of the lower base fabric are each formed by an arc that curves inside the airbag. The airbag, wherein the two connection lines are smoothly connected via a third connection line formed by an arc.